doom writes: "...or nearly anything else you can talk to with DBI. DBI-Link (now up to version 2.0) uses the fact that you can run perl code inside of Postgresql to import external data sources using perl's DBI/DBD system. So Postgresql can use tables from a Mysql database (a reversal of the recent April Fools scenario), which might actually be a practical upgrade path if you were thinking about switching. Or you could have a local Postgresql instance linked with a remote one (perhaps a performance hack, if you're not using replication). Or you can use an LDAP resource like Active Directory as though it were a real database. What I'd really like to see now is a DBD::Emacs. I'm not sure why, but I would."